Figure 1.

The residual stress and surface roughness according to the PZT film thickness. The microstress analysis was measured using the Raman spectra (red circle) taken from the frequencies of E(LO3) Raman modes, whereas the macrostress was calculated using the wafer curvature method (blue triangle). Taken from the AFM images, the rms roughness had a maximum value at a film thickness of 1 μm.

Lee et al. Nanoscale Res Lett 2011 6:55   doi:10.1007/s11671-010-9810-z